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v3.15
   1/*
   2*  Copyright (c) 2004 The Regents of the University of Michigan.
   3*  Copyright (c) 2012 Jeff Layton <jlayton@redhat.com>
   4*  All rights reserved.
   5*
   6*  Andy Adamson <andros@citi.umich.edu>
   7*
   8*  Redistribution and use in source and binary forms, with or without
   9*  modification, are permitted provided that the following conditions
  10*  are met:
  11*
  12*  1. Redistributions of source code must retain the above copyright
  13*     notice, this list of conditions and the following disclaimer.
  14*  2. Redistributions in binary form must reproduce the above copyright
  15*     notice, this list of conditions and the following disclaimer in the
  16*     documentation and/or other materials provided with the distribution.
  17*  3. Neither the name of the University nor the names of its
  18*     contributors may be used to endorse or promote products derived
  19*     from this software without specific prior written permission.
  20*
  21*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  22*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  23*  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  24*  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25*  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  26*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  27*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  28*  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  29*  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30*  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  31*  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32*
  33*/
  34
  35#include <linux/file.h>
  36#include <linux/slab.h>
  37#include <linux/namei.h>
  38#include <linux/crypto.h>
  39#include <linux/sched.h>
  40#include <linux/fs.h>
  41#include <linux/module.h>
  42#include <net/net_namespace.h>
  43#include <linux/sunrpc/rpc_pipe_fs.h>
  44#include <linux/sunrpc/clnt.h>
  45#include <linux/nfsd/cld.h>
  46
  47#include "nfsd.h"
  48#include "state.h"
  49#include "vfs.h"
  50#include "netns.h"
  51
  52#define NFSDDBG_FACILITY                NFSDDBG_PROC
  53
  54/* Declarations */
  55struct nfsd4_client_tracking_ops {
  56	int (*init)(struct net *);
  57	void (*exit)(struct net *);
  58	void (*create)(struct nfs4_client *);
  59	void (*remove)(struct nfs4_client *);
  60	int (*check)(struct nfs4_client *);
  61	void (*grace_done)(struct nfsd_net *, time_t);
  62};
  63
  64/* Globals */
 
  65static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
 
  66
  67static int
  68nfs4_save_creds(const struct cred **original_creds)
  69{
  70	struct cred *new;
  71
  72	new = prepare_creds();
  73	if (!new)
  74		return -ENOMEM;
  75
  76	new->fsuid = GLOBAL_ROOT_UID;
  77	new->fsgid = GLOBAL_ROOT_GID;
  78	*original_creds = override_creds(new);
  79	put_cred(new);
  80	return 0;
  81}
  82
  83static void
  84nfs4_reset_creds(const struct cred *original)
  85{
  86	revert_creds(original);
  87}
  88
  89static void
  90md5_to_hex(char *out, char *md5)
  91{
  92	int i;
  93
  94	for (i=0; i<16; i++) {
  95		unsigned char c = md5[i];
  96
  97		*out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
  98		*out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
  99	}
 100	*out = '\0';
 101}
 102
 103static int
 104nfs4_make_rec_clidname(char *dname, const struct xdr_netobj *clname)
 105{
 106	struct xdr_netobj cksum;
 107	struct hash_desc desc;
 108	struct scatterlist sg;
 109	int status;
 110
 111	dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
 112			clname->len, clname->data);
 113	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
 114	desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
 115	if (IS_ERR(desc.tfm)) {
 116		status = PTR_ERR(desc.tfm);
 117		goto out_no_tfm;
 118	}
 119
 120	cksum.len = crypto_hash_digestsize(desc.tfm);
 121	cksum.data = kmalloc(cksum.len, GFP_KERNEL);
 122	if (cksum.data == NULL) {
 123		status = -ENOMEM;
 124 		goto out;
 125	}
 126
 127	sg_init_one(&sg, clname->data, clname->len);
 128
 129	status = crypto_hash_digest(&desc, &sg, sg.length, cksum.data);
 130	if (status)
 131		goto out;
 132
 133	md5_to_hex(dname, cksum.data);
 134
 135	status = 0;
 136out:
 137	kfree(cksum.data);
 138	crypto_free_hash(desc.tfm);
 139out_no_tfm:
 140	return status;
 141}
 142
 143/*
 144 * If we had an error generating the recdir name for the legacy tracker
 145 * then warn the admin. If the error doesn't appear to be transient,
 146 * then disable recovery tracking.
 147 */
 148static void
 149legacy_recdir_name_error(struct nfs4_client *clp, int error)
 150{
 151	printk(KERN_ERR "NFSD: unable to generate recoverydir "
 152			"name (%d).\n", error);
 153
 154	/*
 155	 * if the algorithm just doesn't exist, then disable the recovery
 156	 * tracker altogether. The crypto libs will generally return this if
 157	 * FIPS is enabled as well.
 158	 */
 159	if (error == -ENOENT) {
 160		printk(KERN_ERR "NFSD: disabling legacy clientid tracking. "
 161			"Reboot recovery will not function correctly!\n");
 162		nfsd4_client_tracking_exit(clp->net);
 163	}
 164}
 165
 166static void
 167nfsd4_create_clid_dir(struct nfs4_client *clp)
 168{
 169	const struct cred *original_cred;
 170	char dname[HEXDIR_LEN];
 171	struct dentry *dir, *dentry;
 172	struct nfs4_client_reclaim *crp;
 173	int status;
 174	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
 175
 176	if (test_and_set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 177		return;
 178	if (!nn->rec_file)
 179		return;
 180
 181	status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 182	if (status)
 183		return legacy_recdir_name_error(clp, status);
 184
 185	status = nfs4_save_creds(&original_cred);
 186	if (status < 0)
 187		return;
 188
 189	status = mnt_want_write_file(nn->rec_file);
 190	if (status)
 191		return;
 192
 193	dir = nn->rec_file->f_path.dentry;
 194	/* lock the parent */
 195	mutex_lock(&dir->d_inode->i_mutex);
 196
 197	dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
 198	if (IS_ERR(dentry)) {
 199		status = PTR_ERR(dentry);
 200		goto out_unlock;
 201	}
 202	if (dentry->d_inode)
 203		/*
 204		 * In the 4.1 case, where we're called from
 205		 * reclaim_complete(), records from the previous reboot
 206		 * may still be left, so this is OK.
 207		 *
 208		 * In the 4.0 case, we should never get here; but we may
 209		 * as well be forgiving and just succeed silently.
 210		 */
 211		goto out_put;
 
 
 
 212	status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU);
 
 213out_put:
 214	dput(dentry);
 215out_unlock:
 216	mutex_unlock(&dir->d_inode->i_mutex);
 217	if (status == 0) {
 218		if (nn->in_grace) {
 219			crp = nfs4_client_to_reclaim(dname, nn);
 220			if (crp)
 221				crp->cr_clp = clp;
 222		}
 223		vfs_fsync(nn->rec_file, 0);
 224	} else {
 225		printk(KERN_ERR "NFSD: failed to write recovery record"
 226				" (err %d); please check that %s exists"
 227				" and is writeable", status,
 228				user_recovery_dirname);
 229	}
 230	mnt_drop_write_file(nn->rec_file);
 231	nfs4_reset_creds(original_cred);
 232}
 233
 234typedef int (recdir_func)(struct dentry *, struct dentry *, struct nfsd_net *);
 235
 236struct name_list {
 237	char name[HEXDIR_LEN];
 238	struct list_head list;
 239};
 240
 241struct nfs4_dir_ctx {
 242	struct dir_context ctx;
 243	struct list_head names;
 244};
 245
 246static int
 247nfsd4_build_namelist(void *arg, const char *name, int namlen,
 248		loff_t offset, u64 ino, unsigned int d_type)
 249{
 250	struct nfs4_dir_ctx *ctx = arg;
 251	struct name_list *entry;
 252
 253	if (namlen != HEXDIR_LEN - 1)
 254		return 0;
 255	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
 256	if (entry == NULL)
 257		return -ENOMEM;
 258	memcpy(entry->name, name, HEXDIR_LEN - 1);
 259	entry->name[HEXDIR_LEN - 1] = '\0';
 260	list_add(&entry->list, &ctx->names);
 261	return 0;
 262}
 263
 264static int
 265nfsd4_list_rec_dir(recdir_func *f, struct nfsd_net *nn)
 266{
 267	const struct cred *original_cred;
 268	struct dentry *dir = nn->rec_file->f_path.dentry;
 269	struct nfs4_dir_ctx ctx = {
 270		.ctx.actor = nfsd4_build_namelist,
 271		.names = LIST_HEAD_INIT(ctx.names)
 272	};
 273	int status;
 274
 275	status = nfs4_save_creds(&original_cred);
 276	if (status < 0)
 277		return status;
 278
 279	status = vfs_llseek(nn->rec_file, 0, SEEK_SET);
 280	if (status < 0) {
 281		nfs4_reset_creds(original_cred);
 282		return status;
 283	}
 284
 285	status = iterate_dir(nn->rec_file, &ctx.ctx);
 286	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
 287	while (!list_empty(&ctx.names)) {
 288		struct name_list *entry;
 289		entry = list_entry(ctx.names.next, struct name_list, list);
 290		if (!status) {
 291			struct dentry *dentry;
 292			dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
 293			if (IS_ERR(dentry)) {
 294				status = PTR_ERR(dentry);
 295				break;
 296			}
 297			status = f(dir, dentry, nn);
 298			dput(dentry);
 299		}
 300		list_del(&entry->list);
 301		kfree(entry);
 302	}
 303	mutex_unlock(&dir->d_inode->i_mutex);
 304	nfs4_reset_creds(original_cred);
 305	return status;
 306}
 307
 308static int
 309nfsd4_unlink_clid_dir(char *name, int namlen, struct nfsd_net *nn)
 310{
 311	struct dentry *dir, *dentry;
 312	int status;
 313
 314	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
 315
 316	dir = nn->rec_file->f_path.dentry;
 317	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
 318	dentry = lookup_one_len(name, dir, namlen);
 319	if (IS_ERR(dentry)) {
 320		status = PTR_ERR(dentry);
 321		goto out_unlock;
 322	}
 323	status = -ENOENT;
 324	if (!dentry->d_inode)
 325		goto out;
 326	status = vfs_rmdir(dir->d_inode, dentry);
 327out:
 328	dput(dentry);
 329out_unlock:
 330	mutex_unlock(&dir->d_inode->i_mutex);
 331	return status;
 332}
 333
 334static void
 335nfsd4_remove_clid_dir(struct nfs4_client *clp)
 336{
 337	const struct cred *original_cred;
 338	struct nfs4_client_reclaim *crp;
 339	char dname[HEXDIR_LEN];
 340	int status;
 341	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 342
 343	if (!nn->rec_file || !test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 344		return;
 345
 346	status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 347	if (status)
 348		return legacy_recdir_name_error(clp, status);
 349
 350	status = mnt_want_write_file(nn->rec_file);
 351	if (status)
 352		goto out;
 353	clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 354
 355	status = nfs4_save_creds(&original_cred);
 356	if (status < 0)
 357		goto out_drop_write;
 358
 359	status = nfsd4_unlink_clid_dir(dname, HEXDIR_LEN-1, nn);
 360	nfs4_reset_creds(original_cred);
 361	if (status == 0) {
 362		vfs_fsync(nn->rec_file, 0);
 363		if (nn->in_grace) {
 364			/* remove reclaim record */
 365			crp = nfsd4_find_reclaim_client(dname, nn);
 366			if (crp)
 367				nfs4_remove_reclaim_record(crp, nn);
 368		}
 369	}
 370out_drop_write:
 371	mnt_drop_write_file(nn->rec_file);
 372out:
 373	if (status)
 374		printk("NFSD: Failed to remove expired client state directory"
 375				" %.*s\n", HEXDIR_LEN, dname);
 376}
 377
 378static int
 379purge_old(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
 380{
 381	int status;
 382
 383	if (nfs4_has_reclaimed_state(child->d_name.name, nn))
 384		return 0;
 385
 386	status = vfs_rmdir(parent->d_inode, child);
 387	if (status)
 388		printk("failed to remove client recovery directory %pd\n",
 389				child);
 390	/* Keep trying, success or failure: */
 391	return 0;
 392}
 393
 394static void
 395nfsd4_recdir_purge_old(struct nfsd_net *nn, time_t boot_time)
 396{
 397	int status;
 398
 399	nn->in_grace = false;
 400	if (!nn->rec_file)
 401		return;
 402	status = mnt_want_write_file(nn->rec_file);
 403	if (status)
 404		goto out;
 405	status = nfsd4_list_rec_dir(purge_old, nn);
 406	if (status == 0)
 407		vfs_fsync(nn->rec_file, 0);
 408	mnt_drop_write_file(nn->rec_file);
 409out:
 410	nfs4_release_reclaim(nn);
 411	if (status)
 412		printk("nfsd4: failed to purge old clients from recovery"
 413			" directory %pD\n", nn->rec_file);
 414}
 415
 416static int
 417load_recdir(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
 418{
 419	if (child->d_name.len != HEXDIR_LEN - 1) {
 420		printk("nfsd4: illegal name %pd in recovery directory\n",
 421				child);
 422		/* Keep trying; maybe the others are OK: */
 423		return 0;
 424	}
 425	nfs4_client_to_reclaim(child->d_name.name, nn);
 426	return 0;
 427}
 428
 429static int
 430nfsd4_recdir_load(struct net *net) {
 431	int status;
 432	struct nfsd_net *nn =  net_generic(net, nfsd_net_id);
 433
 434	if (!nn->rec_file)
 435		return 0;
 436
 437	status = nfsd4_list_rec_dir(load_recdir, nn);
 438	if (status)
 439		printk("nfsd4: failed loading clients from recovery"
 440			" directory %pD\n", nn->rec_file);
 441	return status;
 442}
 443
 444/*
 445 * Hold reference to the recovery directory.
 446 */
 447
 448static int
 449nfsd4_init_recdir(struct net *net)
 450{
 451	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 452	const struct cred *original_cred;
 453	int status;
 454
 455	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
 456			user_recovery_dirname);
 457
 458	BUG_ON(nn->rec_file);
 459
 460	status = nfs4_save_creds(&original_cred);
 461	if (status < 0) {
 462		printk("NFSD: Unable to change credentials to find recovery"
 463		       " directory: error %d\n",
 464		       status);
 465		return status;
 466	}
 467
 468	nn->rec_file = filp_open(user_recovery_dirname, O_RDONLY | O_DIRECTORY, 0);
 469	if (IS_ERR(nn->rec_file)) {
 470		printk("NFSD: unable to find recovery directory %s\n",
 471				user_recovery_dirname);
 472		status = PTR_ERR(nn->rec_file);
 473		nn->rec_file = NULL;
 474	}
 475
 476	nfs4_reset_creds(original_cred);
 477	if (!status)
 478		nn->in_grace = true;
 479	return status;
 480}
 481
 482
 483static int
 484nfs4_legacy_state_init(struct net *net)
 485{
 486	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 487	int i;
 488
 489	nn->reclaim_str_hashtbl = kmalloc(sizeof(struct list_head) *
 490					  CLIENT_HASH_SIZE, GFP_KERNEL);
 491	if (!nn->reclaim_str_hashtbl)
 492		return -ENOMEM;
 493
 494	for (i = 0; i < CLIENT_HASH_SIZE; i++)
 495		INIT_LIST_HEAD(&nn->reclaim_str_hashtbl[i]);
 496	nn->reclaim_str_hashtbl_size = 0;
 497
 498	return 0;
 499}
 500
 501static void
 502nfs4_legacy_state_shutdown(struct net *net)
 503{
 504	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 505
 506	kfree(nn->reclaim_str_hashtbl);
 507}
 508
 509static int
 510nfsd4_load_reboot_recovery_data(struct net *net)
 511{
 512	int status;
 513
 514	status = nfsd4_init_recdir(net);
 515	if (!status)
 516		status = nfsd4_recdir_load(net);
 517	if (status)
 518		printk(KERN_ERR "NFSD: Failure reading reboot recovery data\n");
 519	return status;
 520}
 521
 522static int
 523nfsd4_legacy_tracking_init(struct net *net)
 524{
 525	int status;
 526
 527	/* XXX: The legacy code won't work in a container */
 528	if (net != &init_net) {
 529		WARN(1, KERN_ERR "NFSD: attempt to initialize legacy client "
 530			"tracking in a container!\n");
 531		return -EINVAL;
 532	}
 533
 534	status = nfs4_legacy_state_init(net);
 535	if (status)
 536		return status;
 537
 538	status = nfsd4_load_reboot_recovery_data(net);
 539	if (status)
 540		goto err;
 541	return 0;
 542
 543err:
 544	nfs4_legacy_state_shutdown(net);
 545	return status;
 546}
 547
 548static void
 549nfsd4_shutdown_recdir(struct nfsd_net *nn)
 550{
 551	if (!nn->rec_file)
 552		return;
 553	fput(nn->rec_file);
 554	nn->rec_file = NULL;
 555}
 556
 557static void
 558nfsd4_legacy_tracking_exit(struct net *net)
 559{
 560	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 561
 562	nfs4_release_reclaim(nn);
 563	nfsd4_shutdown_recdir(nn);
 564	nfs4_legacy_state_shutdown(net);
 565}
 566
 567/*
 568 * Change the NFSv4 recovery directory to recdir.
 569 */
 570int
 571nfs4_reset_recoverydir(char *recdir)
 572{
 573	int status;
 574	struct path path;
 575
 576	status = kern_path(recdir, LOOKUP_FOLLOW, &path);
 577	if (status)
 578		return status;
 579	status = -ENOTDIR;
 580	if (S_ISDIR(path.dentry->d_inode->i_mode)) {
 581		strcpy(user_recovery_dirname, recdir);
 582		status = 0;
 583	}
 584	path_put(&path);
 585	return status;
 586}
 587
 588char *
 589nfs4_recoverydir(void)
 590{
 591	return user_recovery_dirname;
 592}
 593
 594static int
 595nfsd4_check_legacy_client(struct nfs4_client *clp)
 596{
 597	int status;
 598	char dname[HEXDIR_LEN];
 599	struct nfs4_client_reclaim *crp;
 600	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 601
 602	/* did we already find that this client is stable? */
 603	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 604		return 0;
 605
 606	status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 607	if (status) {
 608		legacy_recdir_name_error(clp, status);
 609		return status;
 610	}
 611
 612	/* look for it in the reclaim hashtable otherwise */
 613	crp = nfsd4_find_reclaim_client(dname, nn);
 614	if (crp) {
 615		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 616		crp->cr_clp = clp;
 617		return 0;
 618	}
 619
 620	return -ENOENT;
 621}
 622
 623static struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = {
 624	.init		= nfsd4_legacy_tracking_init,
 625	.exit		= nfsd4_legacy_tracking_exit,
 626	.create		= nfsd4_create_clid_dir,
 627	.remove		= nfsd4_remove_clid_dir,
 628	.check		= nfsd4_check_legacy_client,
 629	.grace_done	= nfsd4_recdir_purge_old,
 630};
 631
 632/* Globals */
 633#define NFSD_PIPE_DIR		"nfsd"
 634#define NFSD_CLD_PIPE		"cld"
 635
 636/* per-net-ns structure for holding cld upcall info */
 637struct cld_net {
 638	struct rpc_pipe		*cn_pipe;
 639	spinlock_t		 cn_lock;
 640	struct list_head	 cn_list;
 641	unsigned int		 cn_xid;
 642};
 643
 644struct cld_upcall {
 645	struct list_head	 cu_list;
 646	struct cld_net		*cu_net;
 647	struct task_struct	*cu_task;
 648	struct cld_msg		 cu_msg;
 649};
 650
 651static int
 652__cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg)
 653{
 654	int ret;
 655	struct rpc_pipe_msg msg;
 656
 657	memset(&msg, 0, sizeof(msg));
 658	msg.data = cmsg;
 659	msg.len = sizeof(*cmsg);
 660
 661	/*
 662	 * Set task state before we queue the upcall. That prevents
 663	 * wake_up_process in the downcall from racing with schedule.
 664	 */
 665	set_current_state(TASK_UNINTERRUPTIBLE);
 666	ret = rpc_queue_upcall(pipe, &msg);
 667	if (ret < 0) {
 668		set_current_state(TASK_RUNNING);
 669		goto out;
 670	}
 671
 672	schedule();
 673	set_current_state(TASK_RUNNING);
 674
 675	if (msg.errno < 0)
 676		ret = msg.errno;
 677out:
 678	return ret;
 679}
 680
 681static int
 682cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg)
 683{
 684	int ret;
 685
 686	/*
 687	 * -EAGAIN occurs when pipe is closed and reopened while there are
 688	 *  upcalls queued.
 689	 */
 690	do {
 691		ret = __cld_pipe_upcall(pipe, cmsg);
 692	} while (ret == -EAGAIN);
 693
 694	return ret;
 695}
 696
 697static ssize_t
 698cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 699{
 700	struct cld_upcall *tmp, *cup;
 701	struct cld_msg __user *cmsg = (struct cld_msg __user *)src;
 702	uint32_t xid;
 703	struct nfsd_net *nn = net_generic(filp->f_dentry->d_sb->s_fs_info,
 704						nfsd_net_id);
 705	struct cld_net *cn = nn->cld_net;
 706
 707	if (mlen != sizeof(*cmsg)) {
 708		dprintk("%s: got %zu bytes, expected %zu\n", __func__, mlen,
 709			sizeof(*cmsg));
 710		return -EINVAL;
 711	}
 712
 713	/* copy just the xid so we can try to find that */
 714	if (copy_from_user(&xid, &cmsg->cm_xid, sizeof(xid)) != 0) {
 715		dprintk("%s: error when copying xid from userspace", __func__);
 716		return -EFAULT;
 717	}
 718
 719	/* walk the list and find corresponding xid */
 720	cup = NULL;
 721	spin_lock(&cn->cn_lock);
 722	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
 723		if (get_unaligned(&tmp->cu_msg.cm_xid) == xid) {
 724			cup = tmp;
 725			list_del_init(&cup->cu_list);
 726			break;
 727		}
 728	}
 729	spin_unlock(&cn->cn_lock);
 730
 731	/* couldn't find upcall? */
 732	if (!cup) {
 733		dprintk("%s: couldn't find upcall -- xid=%u\n", __func__, xid);
 734		return -EINVAL;
 735	}
 736
 737	if (copy_from_user(&cup->cu_msg, src, mlen) != 0)
 738		return -EFAULT;
 739
 740	wake_up_process(cup->cu_task);
 741	return mlen;
 742}
 743
 744static void
 745cld_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 746{
 747	struct cld_msg *cmsg = msg->data;
 748	struct cld_upcall *cup = container_of(cmsg, struct cld_upcall,
 749						 cu_msg);
 750
 751	/* errno >= 0 means we got a downcall */
 752	if (msg->errno >= 0)
 753		return;
 754
 755	wake_up_process(cup->cu_task);
 756}
 757
 758static const struct rpc_pipe_ops cld_upcall_ops = {
 759	.upcall		= rpc_pipe_generic_upcall,
 760	.downcall	= cld_pipe_downcall,
 761	.destroy_msg	= cld_pipe_destroy_msg,
 762};
 763
 764static struct dentry *
 765nfsd4_cld_register_sb(struct super_block *sb, struct rpc_pipe *pipe)
 766{
 767	struct dentry *dir, *dentry;
 768
 769	dir = rpc_d_lookup_sb(sb, NFSD_PIPE_DIR);
 770	if (dir == NULL)
 771		return ERR_PTR(-ENOENT);
 772	dentry = rpc_mkpipe_dentry(dir, NFSD_CLD_PIPE, NULL, pipe);
 773	dput(dir);
 774	return dentry;
 775}
 776
 777static void
 778nfsd4_cld_unregister_sb(struct rpc_pipe *pipe)
 779{
 780	if (pipe->dentry)
 781		rpc_unlink(pipe->dentry);
 782}
 783
 784static struct dentry *
 785nfsd4_cld_register_net(struct net *net, struct rpc_pipe *pipe)
 786{
 787	struct super_block *sb;
 788	struct dentry *dentry;
 789
 790	sb = rpc_get_sb_net(net);
 791	if (!sb)
 792		return NULL;
 793	dentry = nfsd4_cld_register_sb(sb, pipe);
 794	rpc_put_sb_net(net);
 795	return dentry;
 796}
 797
 798static void
 799nfsd4_cld_unregister_net(struct net *net, struct rpc_pipe *pipe)
 800{
 801	struct super_block *sb;
 802
 803	sb = rpc_get_sb_net(net);
 804	if (sb) {
 805		nfsd4_cld_unregister_sb(pipe);
 806		rpc_put_sb_net(net);
 807	}
 808}
 809
 810/* Initialize rpc_pipefs pipe for communication with client tracking daemon */
 811static int
 812nfsd4_init_cld_pipe(struct net *net)
 813{
 814	int ret;
 815	struct dentry *dentry;
 816	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 817	struct cld_net *cn;
 818
 819	if (nn->cld_net)
 820		return 0;
 821
 822	cn = kzalloc(sizeof(*cn), GFP_KERNEL);
 823	if (!cn) {
 824		ret = -ENOMEM;
 825		goto err;
 826	}
 827
 828	cn->cn_pipe = rpc_mkpipe_data(&cld_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
 829	if (IS_ERR(cn->cn_pipe)) {
 830		ret = PTR_ERR(cn->cn_pipe);
 831		goto err;
 832	}
 833	spin_lock_init(&cn->cn_lock);
 834	INIT_LIST_HEAD(&cn->cn_list);
 835
 836	dentry = nfsd4_cld_register_net(net, cn->cn_pipe);
 837	if (IS_ERR(dentry)) {
 838		ret = PTR_ERR(dentry);
 839		goto err_destroy_data;
 840	}
 841
 842	cn->cn_pipe->dentry = dentry;
 843	nn->cld_net = cn;
 844	return 0;
 845
 846err_destroy_data:
 847	rpc_destroy_pipe_data(cn->cn_pipe);
 848err:
 849	kfree(cn);
 850	printk(KERN_ERR "NFSD: unable to create nfsdcld upcall pipe (%d)\n",
 851			ret);
 852	return ret;
 853}
 854
 855static void
 856nfsd4_remove_cld_pipe(struct net *net)
 857{
 858	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 859	struct cld_net *cn = nn->cld_net;
 860
 861	nfsd4_cld_unregister_net(net, cn->cn_pipe);
 862	rpc_destroy_pipe_data(cn->cn_pipe);
 863	kfree(nn->cld_net);
 864	nn->cld_net = NULL;
 865}
 866
 867static struct cld_upcall *
 868alloc_cld_upcall(struct cld_net *cn)
 869{
 870	struct cld_upcall *new, *tmp;
 871
 872	new = kzalloc(sizeof(*new), GFP_KERNEL);
 873	if (!new)
 874		return new;
 875
 876	/* FIXME: hard cap on number in flight? */
 877restart_search:
 878	spin_lock(&cn->cn_lock);
 879	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
 880		if (tmp->cu_msg.cm_xid == cn->cn_xid) {
 881			cn->cn_xid++;
 882			spin_unlock(&cn->cn_lock);
 883			goto restart_search;
 884		}
 885	}
 886	new->cu_task = current;
 887	new->cu_msg.cm_vers = CLD_UPCALL_VERSION;
 888	put_unaligned(cn->cn_xid++, &new->cu_msg.cm_xid);
 889	new->cu_net = cn;
 890	list_add(&new->cu_list, &cn->cn_list);
 891	spin_unlock(&cn->cn_lock);
 892
 893	dprintk("%s: allocated xid %u\n", __func__, new->cu_msg.cm_xid);
 894
 895	return new;
 896}
 897
 898static void
 899free_cld_upcall(struct cld_upcall *victim)
 900{
 901	struct cld_net *cn = victim->cu_net;
 902
 903	spin_lock(&cn->cn_lock);
 904	list_del(&victim->cu_list);
 905	spin_unlock(&cn->cn_lock);
 906	kfree(victim);
 907}
 908
 909/* Ask daemon to create a new record */
 910static void
 911nfsd4_cld_create(struct nfs4_client *clp)
 912{
 913	int ret;
 914	struct cld_upcall *cup;
 915	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
 916	struct cld_net *cn = nn->cld_net;
 917
 918	/* Don't upcall if it's already stored */
 919	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 920		return;
 921
 922	cup = alloc_cld_upcall(cn);
 923	if (!cup) {
 924		ret = -ENOMEM;
 925		goto out_err;
 926	}
 927
 928	cup->cu_msg.cm_cmd = Cld_Create;
 929	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
 930	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
 931			clp->cl_name.len);
 932
 933	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
 934	if (!ret) {
 935		ret = cup->cu_msg.cm_status;
 936		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 937	}
 938
 939	free_cld_upcall(cup);
 940out_err:
 941	if (ret)
 942		printk(KERN_ERR "NFSD: Unable to create client "
 943				"record on stable storage: %d\n", ret);
 944}
 945
 946/* Ask daemon to create a new record */
 947static void
 948nfsd4_cld_remove(struct nfs4_client *clp)
 949{
 950	int ret;
 951	struct cld_upcall *cup;
 952	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
 953	struct cld_net *cn = nn->cld_net;
 954
 955	/* Don't upcall if it's already removed */
 956	if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 957		return;
 958
 959	cup = alloc_cld_upcall(cn);
 960	if (!cup) {
 961		ret = -ENOMEM;
 962		goto out_err;
 963	}
 964
 965	cup->cu_msg.cm_cmd = Cld_Remove;
 966	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
 967	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
 968			clp->cl_name.len);
 969
 970	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
 971	if (!ret) {
 972		ret = cup->cu_msg.cm_status;
 973		clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 974	}
 975
 976	free_cld_upcall(cup);
 977out_err:
 978	if (ret)
 979		printk(KERN_ERR "NFSD: Unable to remove client "
 980				"record from stable storage: %d\n", ret);
 981}
 982
 983/* Check for presence of a record, and update its timestamp */
 984static int
 985nfsd4_cld_check(struct nfs4_client *clp)
 986{
 987	int ret;
 988	struct cld_upcall *cup;
 989	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
 990	struct cld_net *cn = nn->cld_net;
 991
 992	/* Don't upcall if one was already stored during this grace pd */
 993	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 994		return 0;
 995
 996	cup = alloc_cld_upcall(cn);
 997	if (!cup) {
 998		printk(KERN_ERR "NFSD: Unable to check client record on "
 999				"stable storage: %d\n", -ENOMEM);
1000		return -ENOMEM;
1001	}
1002
1003	cup->cu_msg.cm_cmd = Cld_Check;
1004	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
1005	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
1006			clp->cl_name.len);
1007
1008	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
1009	if (!ret) {
1010		ret = cup->cu_msg.cm_status;
1011		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1012	}
1013
1014	free_cld_upcall(cup);
1015	return ret;
1016}
1017
1018static void
1019nfsd4_cld_grace_done(struct nfsd_net *nn, time_t boot_time)
1020{
1021	int ret;
1022	struct cld_upcall *cup;
 
1023	struct cld_net *cn = nn->cld_net;
1024
1025	cup = alloc_cld_upcall(cn);
1026	if (!cup) {
1027		ret = -ENOMEM;
1028		goto out_err;
1029	}
1030
1031	cup->cu_msg.cm_cmd = Cld_GraceDone;
1032	cup->cu_msg.cm_u.cm_gracetime = (int64_t)boot_time;
1033	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
1034	if (!ret)
1035		ret = cup->cu_msg.cm_status;
1036
1037	free_cld_upcall(cup);
1038out_err:
1039	if (ret)
1040		printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret);
1041}
1042
1043static struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = {
1044	.init		= nfsd4_init_cld_pipe,
1045	.exit		= nfsd4_remove_cld_pipe,
1046	.create		= nfsd4_cld_create,
1047	.remove		= nfsd4_cld_remove,
1048	.check		= nfsd4_cld_check,
1049	.grace_done	= nfsd4_cld_grace_done,
1050};
1051
1052/* upcall via usermodehelper */
1053static char cltrack_prog[PATH_MAX] = "/sbin/nfsdcltrack";
1054module_param_string(cltrack_prog, cltrack_prog, sizeof(cltrack_prog),
1055			S_IRUGO|S_IWUSR);
1056MODULE_PARM_DESC(cltrack_prog, "Path to the nfsdcltrack upcall program");
1057
1058static bool cltrack_legacy_disable;
1059module_param(cltrack_legacy_disable, bool, S_IRUGO|S_IWUSR);
1060MODULE_PARM_DESC(cltrack_legacy_disable,
1061		"Disable legacy recoverydir conversion. Default: false");
1062
1063#define LEGACY_TOPDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_TOPDIR="
1064#define LEGACY_RECDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_RECDIR="
1065
1066static char *
1067nfsd4_cltrack_legacy_topdir(void)
1068{
1069	int copied;
1070	size_t len;
1071	char *result;
1072
1073	if (cltrack_legacy_disable)
1074		return NULL;
1075
1076	len = strlen(LEGACY_TOPDIR_ENV_PREFIX) +
1077		strlen(nfs4_recoverydir()) + 1;
1078
1079	result = kmalloc(len, GFP_KERNEL);
1080	if (!result)
1081		return result;
1082
1083	copied = snprintf(result, len, LEGACY_TOPDIR_ENV_PREFIX "%s",
1084				nfs4_recoverydir());
1085	if (copied >= len) {
1086		/* just return nothing if output was truncated */
1087		kfree(result);
1088		return NULL;
1089	}
1090
1091	return result;
1092}
1093
1094static char *
1095nfsd4_cltrack_legacy_recdir(const struct xdr_netobj *name)
1096{
1097	int copied;
1098	size_t len;
1099	char *result;
1100
1101	if (cltrack_legacy_disable)
1102		return NULL;
1103
1104	/* +1 is for '/' between "topdir" and "recdir" */
1105	len = strlen(LEGACY_RECDIR_ENV_PREFIX) +
1106		strlen(nfs4_recoverydir()) + 1 + HEXDIR_LEN;
1107
1108	result = kmalloc(len, GFP_KERNEL);
1109	if (!result)
1110		return result;
1111
1112	copied = snprintf(result, len, LEGACY_RECDIR_ENV_PREFIX "%s/",
1113				nfs4_recoverydir());
1114	if (copied > (len - HEXDIR_LEN)) {
1115		/* just return nothing if output will be truncated */
1116		kfree(result);
1117		return NULL;
1118	}
1119
1120	copied = nfs4_make_rec_clidname(result + copied, name);
1121	if (copied) {
1122		kfree(result);
1123		return NULL;
1124	}
1125
1126	return result;
1127}
1128
1129static int
1130nfsd4_umh_cltrack_upcall(char *cmd, char *arg, char *legacy)
1131{
1132	char *envp[2];
1133	char *argv[4];
1134	int ret;
1135
1136	if (unlikely(!cltrack_prog[0])) {
1137		dprintk("%s: cltrack_prog is disabled\n", __func__);
1138		return -EACCES;
1139	}
1140
1141	dprintk("%s: cmd: %s\n", __func__, cmd);
1142	dprintk("%s: arg: %s\n", __func__, arg ? arg : "(null)");
1143	dprintk("%s: legacy: %s\n", __func__, legacy ? legacy : "(null)");
1144
1145	envp[0] = legacy;
1146	envp[1] = NULL;
1147
1148	argv[0] = (char *)cltrack_prog;
1149	argv[1] = cmd;
1150	argv[2] = arg;
1151	argv[3] = NULL;
1152
1153	ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
1154	/*
1155	 * Disable the upcall mechanism if we're getting an ENOENT or EACCES
1156	 * error. The admin can re-enable it on the fly by using sysfs
1157	 * once the problem has been fixed.
1158	 */
1159	if (ret == -ENOENT || ret == -EACCES) {
1160		dprintk("NFSD: %s was not found or isn't executable (%d). "
1161			"Setting cltrack_prog to blank string!",
1162			cltrack_prog, ret);
1163		cltrack_prog[0] = '\0';
1164	}
1165	dprintk("%s: %s return value: %d\n", __func__, cltrack_prog, ret);
1166
1167	return ret;
1168}
1169
1170static char *
1171bin_to_hex_dup(const unsigned char *src, int srclen)
1172{
1173	int i;
1174	char *buf, *hex;
1175
1176	/* +1 for terminating NULL */
1177	buf = kmalloc((srclen * 2) + 1, GFP_KERNEL);
1178	if (!buf)
1179		return buf;
1180
1181	hex = buf;
1182	for (i = 0; i < srclen; i++) {
1183		sprintf(hex, "%2.2x", *src++);
1184		hex += 2;
1185	}
1186	return buf;
1187}
1188
1189static int
1190nfsd4_umh_cltrack_init(struct net __attribute__((unused)) *net)
1191{
1192	/* XXX: The usermode helper s not working in container yet. */
1193	if (net != &init_net) {
1194		WARN(1, KERN_ERR "NFSD: attempt to initialize umh client "
1195			"tracking in a container!\n");
1196		return -EINVAL;
1197	}
1198	return nfsd4_umh_cltrack_upcall("init", NULL, NULL);
1199}
1200
1201static void
1202nfsd4_umh_cltrack_create(struct nfs4_client *clp)
1203{
1204	char *hexid;
1205
1206	hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1207	if (!hexid) {
1208		dprintk("%s: can't allocate memory for upcall!\n", __func__);
1209		return;
1210	}
1211	nfsd4_umh_cltrack_upcall("create", hexid, NULL);
1212	kfree(hexid);
1213}
1214
1215static void
1216nfsd4_umh_cltrack_remove(struct nfs4_client *clp)
1217{
1218	char *hexid;
1219
1220	hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1221	if (!hexid) {
1222		dprintk("%s: can't allocate memory for upcall!\n", __func__);
1223		return;
1224	}
1225	nfsd4_umh_cltrack_upcall("remove", hexid, NULL);
1226	kfree(hexid);
1227}
1228
1229static int
1230nfsd4_umh_cltrack_check(struct nfs4_client *clp)
1231{
1232	int ret;
1233	char *hexid, *legacy;
1234
1235	hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1236	if (!hexid) {
1237		dprintk("%s: can't allocate memory for upcall!\n", __func__);
1238		return -ENOMEM;
1239	}
1240	legacy = nfsd4_cltrack_legacy_recdir(&clp->cl_name);
1241	ret = nfsd4_umh_cltrack_upcall("check", hexid, legacy);
1242	kfree(legacy);
1243	kfree(hexid);
1244	return ret;
1245}
1246
1247static void
1248nfsd4_umh_cltrack_grace_done(struct nfsd_net __attribute__((unused)) *nn,
1249				time_t boot_time)
1250{
1251	char *legacy;
1252	char timestr[22]; /* FIXME: better way to determine max size? */
1253
1254	sprintf(timestr, "%ld", boot_time);
1255	legacy = nfsd4_cltrack_legacy_topdir();
1256	nfsd4_umh_cltrack_upcall("gracedone", timestr, legacy);
1257	kfree(legacy);
1258}
1259
1260static struct nfsd4_client_tracking_ops nfsd4_umh_tracking_ops = {
1261	.init		= nfsd4_umh_cltrack_init,
1262	.exit		= NULL,
1263	.create		= nfsd4_umh_cltrack_create,
1264	.remove		= nfsd4_umh_cltrack_remove,
1265	.check		= nfsd4_umh_cltrack_check,
1266	.grace_done	= nfsd4_umh_cltrack_grace_done,
1267};
1268
1269int
1270nfsd4_client_tracking_init(struct net *net)
1271{
1272	int status;
1273	struct path path;
1274	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1275
1276	/* just run the init if it the method is already decided */
1277	if (nn->client_tracking_ops)
1278		goto do_init;
1279
1280	/*
1281	 * First, try a UMH upcall. It should succeed or fail quickly, so
1282	 * there's little harm in trying that first.
1283	 */
1284	nn->client_tracking_ops = &nfsd4_umh_tracking_ops;
1285	status = nn->client_tracking_ops->init(net);
1286	if (!status)
1287		return status;
 
 
1288
1289	/*
1290	 * See if the recoverydir exists and is a directory. If it is,
1291	 * then use the legacy ops.
1292	 */
1293	nn->client_tracking_ops = &nfsd4_legacy_tracking_ops;
1294	status = kern_path(nfs4_recoverydir(), LOOKUP_FOLLOW, &path);
1295	if (!status) {
1296		status = S_ISDIR(path.dentry->d_inode->i_mode);
1297		path_put(&path);
1298		if (status)
1299			goto do_init;
1300	}
1301
1302	/* Finally, try to use nfsdcld */
1303	nn->client_tracking_ops = &nfsd4_cld_tracking_ops;
1304	printk(KERN_WARNING "NFSD: the nfsdcld client tracking upcall will be "
1305			"removed in 3.10. Please transition to using "
1306			"nfsdcltrack.\n");
1307do_init:
1308	status = nn->client_tracking_ops->init(net);
1309	if (status) {
1310		printk(KERN_WARNING "NFSD: Unable to initialize client "
1311				    "recovery tracking! (%d)\n", status);
1312		nn->client_tracking_ops = NULL;
1313	}
1314	return status;
1315}
1316
1317void
1318nfsd4_client_tracking_exit(struct net *net)
1319{
1320	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1321
1322	if (nn->client_tracking_ops) {
1323		if (nn->client_tracking_ops->exit)
1324			nn->client_tracking_ops->exit(net);
1325		nn->client_tracking_ops = NULL;
1326	}
1327}
1328
1329void
1330nfsd4_client_record_create(struct nfs4_client *clp)
1331{
1332	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1333
1334	if (nn->client_tracking_ops)
1335		nn->client_tracking_ops->create(clp);
1336}
1337
1338void
1339nfsd4_client_record_remove(struct nfs4_client *clp)
1340{
1341	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1342
1343	if (nn->client_tracking_ops)
1344		nn->client_tracking_ops->remove(clp);
1345}
1346
1347int
1348nfsd4_client_record_check(struct nfs4_client *clp)
1349{
1350	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1351
1352	if (nn->client_tracking_ops)
1353		return nn->client_tracking_ops->check(clp);
1354
1355	return -EOPNOTSUPP;
1356}
1357
1358void
1359nfsd4_record_grace_done(struct nfsd_net *nn, time_t boot_time)
1360{
1361	if (nn->client_tracking_ops)
1362		nn->client_tracking_ops->grace_done(nn, boot_time);
1363}
1364
1365static int
1366rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr)
1367{
1368	struct super_block *sb = ptr;
1369	struct net *net = sb->s_fs_info;
1370	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1371	struct cld_net *cn = nn->cld_net;
1372	struct dentry *dentry;
1373	int ret = 0;
1374
1375	if (!try_module_get(THIS_MODULE))
1376		return 0;
1377
1378	if (!cn) {
1379		module_put(THIS_MODULE);
1380		return 0;
1381	}
1382
1383	switch (event) {
1384	case RPC_PIPEFS_MOUNT:
1385		dentry = nfsd4_cld_register_sb(sb, cn->cn_pipe);
1386		if (IS_ERR(dentry)) {
1387			ret = PTR_ERR(dentry);
1388			break;
1389		}
1390		cn->cn_pipe->dentry = dentry;
1391		break;
1392	case RPC_PIPEFS_UMOUNT:
1393		if (cn->cn_pipe->dentry)
1394			nfsd4_cld_unregister_sb(cn->cn_pipe);
1395		break;
1396	default:
1397		ret = -ENOTSUPP;
1398		break;
1399	}
1400	module_put(THIS_MODULE);
1401	return ret;
1402}
1403
1404static struct notifier_block nfsd4_cld_block = {
1405	.notifier_call = rpc_pipefs_event,
1406};
1407
1408int
1409register_cld_notifier(void)
1410{
1411	return rpc_pipefs_notifier_register(&nfsd4_cld_block);
1412}
1413
1414void
1415unregister_cld_notifier(void)
1416{
1417	rpc_pipefs_notifier_unregister(&nfsd4_cld_block);
1418}
v3.5.6
   1/*
   2*  Copyright (c) 2004 The Regents of the University of Michigan.
   3*  Copyright (c) 2012 Jeff Layton <jlayton@redhat.com>
   4*  All rights reserved.
   5*
   6*  Andy Adamson <andros@citi.umich.edu>
   7*
   8*  Redistribution and use in source and binary forms, with or without
   9*  modification, are permitted provided that the following conditions
  10*  are met:
  11*
  12*  1. Redistributions of source code must retain the above copyright
  13*     notice, this list of conditions and the following disclaimer.
  14*  2. Redistributions in binary form must reproduce the above copyright
  15*     notice, this list of conditions and the following disclaimer in the
  16*     documentation and/or other materials provided with the distribution.
  17*  3. Neither the name of the University nor the names of its
  18*     contributors may be used to endorse or promote products derived
  19*     from this software without specific prior written permission.
  20*
  21*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  22*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  23*  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  24*  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25*  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  26*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  27*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  28*  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  29*  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30*  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  31*  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32*
  33*/
  34
  35#include <linux/file.h>
  36#include <linux/slab.h>
  37#include <linux/namei.h>
  38#include <linux/crypto.h>
  39#include <linux/sched.h>
  40#include <linux/fs.h>
  41#include <linux/module.h>
  42#include <net/net_namespace.h>
  43#include <linux/sunrpc/rpc_pipe_fs.h>
  44#include <linux/sunrpc/clnt.h>
  45#include <linux/nfsd/cld.h>
  46
  47#include "nfsd.h"
  48#include "state.h"
  49#include "vfs.h"
  50#include "netns.h"
  51
  52#define NFSDDBG_FACILITY                NFSDDBG_PROC
  53
  54/* Declarations */
  55struct nfsd4_client_tracking_ops {
  56	int (*init)(struct net *);
  57	void (*exit)(struct net *);
  58	void (*create)(struct nfs4_client *);
  59	void (*remove)(struct nfs4_client *);
  60	int (*check)(struct nfs4_client *);
  61	void (*grace_done)(struct net *, time_t);
  62};
  63
  64/* Globals */
  65static struct file *rec_file;
  66static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
  67static struct nfsd4_client_tracking_ops *client_tracking_ops;
  68
  69static int
  70nfs4_save_creds(const struct cred **original_creds)
  71{
  72	struct cred *new;
  73
  74	new = prepare_creds();
  75	if (!new)
  76		return -ENOMEM;
  77
  78	new->fsuid = 0;
  79	new->fsgid = 0;
  80	*original_creds = override_creds(new);
  81	put_cred(new);
  82	return 0;
  83}
  84
  85static void
  86nfs4_reset_creds(const struct cred *original)
  87{
  88	revert_creds(original);
  89}
  90
  91static void
  92md5_to_hex(char *out, char *md5)
  93{
  94	int i;
  95
  96	for (i=0; i<16; i++) {
  97		unsigned char c = md5[i];
  98
  99		*out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
 100		*out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
 101	}
 102	*out = '\0';
 103}
 104
 105__be32
 106nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
 107{
 108	struct xdr_netobj cksum;
 109	struct hash_desc desc;
 110	struct scatterlist sg;
 111	__be32 status = nfserr_jukebox;
 112
 113	dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
 114			clname->len, clname->data);
 115	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
 116	desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
 117	if (IS_ERR(desc.tfm))
 
 118		goto out_no_tfm;
 
 
 119	cksum.len = crypto_hash_digestsize(desc.tfm);
 120	cksum.data = kmalloc(cksum.len, GFP_KERNEL);
 121	if (cksum.data == NULL)
 
 122 		goto out;
 
 123
 124	sg_init_one(&sg, clname->data, clname->len);
 125
 126	if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
 
 127		goto out;
 128
 129	md5_to_hex(dname, cksum.data);
 130
 131	status = nfs_ok;
 132out:
 133	kfree(cksum.data);
 134	crypto_free_hash(desc.tfm);
 135out_no_tfm:
 136	return status;
 137}
 138
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 139static void
 140nfsd4_create_clid_dir(struct nfs4_client *clp)
 141{
 142	const struct cred *original_cred;
 143	char *dname = clp->cl_recdir;
 144	struct dentry *dir, *dentry;
 
 145	int status;
 146
 147	dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
 148
 149	if (test_and_set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 150		return;
 151	if (!rec_file)
 152		return;
 
 
 
 
 
 153	status = nfs4_save_creds(&original_cred);
 154	if (status < 0)
 155		return;
 156
 157	dir = rec_file->f_path.dentry;
 
 
 
 
 158	/* lock the parent */
 159	mutex_lock(&dir->d_inode->i_mutex);
 160
 161	dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
 162	if (IS_ERR(dentry)) {
 163		status = PTR_ERR(dentry);
 164		goto out_unlock;
 165	}
 166	if (dentry->d_inode)
 167		/*
 168		 * In the 4.1 case, where we're called from
 169		 * reclaim_complete(), records from the previous reboot
 170		 * may still be left, so this is OK.
 171		 *
 172		 * In the 4.0 case, we should never get here; but we may
 173		 * as well be forgiving and just succeed silently.
 174		 */
 175		goto out_put;
 176	status = mnt_want_write_file(rec_file);
 177	if (status)
 178		goto out_put;
 179	status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU);
 180	mnt_drop_write_file(rec_file);
 181out_put:
 182	dput(dentry);
 183out_unlock:
 184	mutex_unlock(&dir->d_inode->i_mutex);
 185	if (status == 0)
 186		vfs_fsync(rec_file, 0);
 187	else
 
 
 
 
 
 188		printk(KERN_ERR "NFSD: failed to write recovery record"
 189				" (err %d); please check that %s exists"
 190				" and is writeable", status,
 191				user_recovery_dirname);
 
 
 192	nfs4_reset_creds(original_cred);
 193}
 194
 195typedef int (recdir_func)(struct dentry *, struct dentry *);
 196
 197struct name_list {
 198	char name[HEXDIR_LEN];
 199	struct list_head list;
 200};
 201
 
 
 
 
 
 202static int
 203nfsd4_build_namelist(void *arg, const char *name, int namlen,
 204		loff_t offset, u64 ino, unsigned int d_type)
 205{
 206	struct list_head *names = arg;
 207	struct name_list *entry;
 208
 209	if (namlen != HEXDIR_LEN - 1)
 210		return 0;
 211	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
 212	if (entry == NULL)
 213		return -ENOMEM;
 214	memcpy(entry->name, name, HEXDIR_LEN - 1);
 215	entry->name[HEXDIR_LEN - 1] = '\0';
 216	list_add(&entry->list, names);
 217	return 0;
 218}
 219
 220static int
 221nfsd4_list_rec_dir(recdir_func *f)
 222{
 223	const struct cred *original_cred;
 224	struct dentry *dir = rec_file->f_path.dentry;
 225	LIST_HEAD(names);
 
 
 
 226	int status;
 227
 228	status = nfs4_save_creds(&original_cred);
 229	if (status < 0)
 230		return status;
 231
 232	status = vfs_llseek(rec_file, 0, SEEK_SET);
 233	if (status < 0) {
 234		nfs4_reset_creds(original_cred);
 235		return status;
 236	}
 237
 238	status = vfs_readdir(rec_file, nfsd4_build_namelist, &names);
 239	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
 240	while (!list_empty(&names)) {
 241		struct name_list *entry;
 242		entry = list_entry(names.next, struct name_list, list);
 243		if (!status) {
 244			struct dentry *dentry;
 245			dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
 246			if (IS_ERR(dentry)) {
 247				status = PTR_ERR(dentry);
 248				break;
 249			}
 250			status = f(dir, dentry);
 251			dput(dentry);
 252		}
 253		list_del(&entry->list);
 254		kfree(entry);
 255	}
 256	mutex_unlock(&dir->d_inode->i_mutex);
 257	nfs4_reset_creds(original_cred);
 258	return status;
 259}
 260
 261static int
 262nfsd4_unlink_clid_dir(char *name, int namlen)
 263{
 264	struct dentry *dir, *dentry;
 265	int status;
 266
 267	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
 268
 269	dir = rec_file->f_path.dentry;
 270	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
 271	dentry = lookup_one_len(name, dir, namlen);
 272	if (IS_ERR(dentry)) {
 273		status = PTR_ERR(dentry);
 274		goto out_unlock;
 275	}
 276	status = -ENOENT;
 277	if (!dentry->d_inode)
 278		goto out;
 279	status = vfs_rmdir(dir->d_inode, dentry);
 280out:
 281	dput(dentry);
 282out_unlock:
 283	mutex_unlock(&dir->d_inode->i_mutex);
 284	return status;
 285}
 286
 287static void
 288nfsd4_remove_clid_dir(struct nfs4_client *clp)
 289{
 290	const struct cred *original_cred;
 
 
 291	int status;
 
 292
 293	if (!rec_file || !test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 294		return;
 295
 296	status = mnt_want_write_file(rec_file);
 
 
 
 
 297	if (status)
 298		goto out;
 299	clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 300
 301	status = nfs4_save_creds(&original_cred);
 302	if (status < 0)
 303		goto out;
 304
 305	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
 306	nfs4_reset_creds(original_cred);
 307	if (status == 0)
 308		vfs_fsync(rec_file, 0);
 309	mnt_drop_write_file(rec_file);
 
 
 
 
 
 
 
 
 310out:
 311	if (status)
 312		printk("NFSD: Failed to remove expired client state directory"
 313				" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
 314}
 315
 316static int
 317purge_old(struct dentry *parent, struct dentry *child)
 318{
 319	int status;
 320
 321	if (nfs4_has_reclaimed_state(child->d_name.name, false))
 322		return 0;
 323
 324	status = vfs_rmdir(parent->d_inode, child);
 325	if (status)
 326		printk("failed to remove client recovery directory %s\n",
 327				child->d_name.name);
 328	/* Keep trying, success or failure: */
 329	return 0;
 330}
 331
 332static void
 333nfsd4_recdir_purge_old(struct net *net, time_t boot_time)
 334{
 335	int status;
 336
 337	if (!rec_file)
 
 338		return;
 339	status = mnt_want_write_file(rec_file);
 340	if (status)
 341		goto out;
 342	status = nfsd4_list_rec_dir(purge_old);
 343	if (status == 0)
 344		vfs_fsync(rec_file, 0);
 345	mnt_drop_write_file(rec_file);
 346out:
 
 347	if (status)
 348		printk("nfsd4: failed to purge old clients from recovery"
 349			" directory %s\n", rec_file->f_path.dentry->d_name.name);
 350}
 351
 352static int
 353load_recdir(struct dentry *parent, struct dentry *child)
 354{
 355	if (child->d_name.len != HEXDIR_LEN - 1) {
 356		printk("nfsd4: illegal name %s in recovery directory\n",
 357				child->d_name.name);
 358		/* Keep trying; maybe the others are OK: */
 359		return 0;
 360	}
 361	nfs4_client_to_reclaim(child->d_name.name);
 362	return 0;
 363}
 364
 365static int
 366nfsd4_recdir_load(void) {
 367	int status;
 
 368
 369	if (!rec_file)
 370		return 0;
 371
 372	status = nfsd4_list_rec_dir(load_recdir);
 373	if (status)
 374		printk("nfsd4: failed loading clients from recovery"
 375			" directory %s\n", rec_file->f_path.dentry->d_name.name);
 376	return status;
 377}
 378
 379/*
 380 * Hold reference to the recovery directory.
 381 */
 382
 383static int
 384nfsd4_init_recdir(void)
 385{
 
 386	const struct cred *original_cred;
 387	int status;
 388
 389	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
 390			user_recovery_dirname);
 391
 392	BUG_ON(rec_file);
 393
 394	status = nfs4_save_creds(&original_cred);
 395	if (status < 0) {
 396		printk("NFSD: Unable to change credentials to find recovery"
 397		       " directory: error %d\n",
 398		       status);
 399		return status;
 400	}
 401
 402	rec_file = filp_open(user_recovery_dirname, O_RDONLY | O_DIRECTORY, 0);
 403	if (IS_ERR(rec_file)) {
 404		printk("NFSD: unable to find recovery directory %s\n",
 405				user_recovery_dirname);
 406		status = PTR_ERR(rec_file);
 407		rec_file = NULL;
 408	}
 409
 410	nfs4_reset_creds(original_cred);
 
 
 411	return status;
 412}
 413
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 414static int
 415nfsd4_load_reboot_recovery_data(struct net *net)
 416{
 417	int status;
 418
 
 
 
 
 
 
 
 
 
 
 
 
 
 419	/* XXX: The legacy code won't work in a container */
 420	if (net != &init_net) {
 421		WARN(1, KERN_ERR "NFSD: attempt to initialize legacy client "
 422			"tracking in a container!\n");
 423		return -EINVAL;
 424	}
 425
 426	nfs4_lock_state();
 427	status = nfsd4_init_recdir();
 428	if (!status)
 429		status = nfsd4_recdir_load();
 430	nfs4_unlock_state();
 431	if (status)
 432		printk(KERN_ERR "NFSD: Failure reading reboot recovery data\n");
 
 
 
 
 433	return status;
 434}
 435
 436static void
 437nfsd4_shutdown_recdir(void)
 438{
 439	if (!rec_file)
 440		return;
 441	fput(rec_file);
 442	rec_file = NULL;
 443}
 444
 445static void
 446nfsd4_legacy_tracking_exit(struct net *net)
 447{
 448	nfs4_release_reclaim();
 449	nfsd4_shutdown_recdir();
 
 
 
 450}
 451
 452/*
 453 * Change the NFSv4 recovery directory to recdir.
 454 */
 455int
 456nfs4_reset_recoverydir(char *recdir)
 457{
 458	int status;
 459	struct path path;
 460
 461	status = kern_path(recdir, LOOKUP_FOLLOW, &path);
 462	if (status)
 463		return status;
 464	status = -ENOTDIR;
 465	if (S_ISDIR(path.dentry->d_inode->i_mode)) {
 466		strcpy(user_recovery_dirname, recdir);
 467		status = 0;
 468	}
 469	path_put(&path);
 470	return status;
 471}
 472
 473char *
 474nfs4_recoverydir(void)
 475{
 476	return user_recovery_dirname;
 477}
 478
 479static int
 480nfsd4_check_legacy_client(struct nfs4_client *clp)
 481{
 
 
 
 
 
 482	/* did we already find that this client is stable? */
 483	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 484		return 0;
 485
 
 
 
 
 
 
 486	/* look for it in the reclaim hashtable otherwise */
 487	if (nfsd4_find_reclaim_client(clp)) {
 
 488		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 
 489		return 0;
 490	}
 491
 492	return -ENOENT;
 493}
 494
 495static struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = {
 496	.init		= nfsd4_load_reboot_recovery_data,
 497	.exit		= nfsd4_legacy_tracking_exit,
 498	.create		= nfsd4_create_clid_dir,
 499	.remove		= nfsd4_remove_clid_dir,
 500	.check		= nfsd4_check_legacy_client,
 501	.grace_done	= nfsd4_recdir_purge_old,
 502};
 503
 504/* Globals */
 505#define NFSD_PIPE_DIR		"nfsd"
 506#define NFSD_CLD_PIPE		"cld"
 507
 508/* per-net-ns structure for holding cld upcall info */
 509struct cld_net {
 510	struct rpc_pipe		*cn_pipe;
 511	spinlock_t		 cn_lock;
 512	struct list_head	 cn_list;
 513	unsigned int		 cn_xid;
 514};
 515
 516struct cld_upcall {
 517	struct list_head	 cu_list;
 518	struct cld_net		*cu_net;
 519	struct task_struct	*cu_task;
 520	struct cld_msg		 cu_msg;
 521};
 522
 523static int
 524__cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg)
 525{
 526	int ret;
 527	struct rpc_pipe_msg msg;
 528
 529	memset(&msg, 0, sizeof(msg));
 530	msg.data = cmsg;
 531	msg.len = sizeof(*cmsg);
 532
 533	/*
 534	 * Set task state before we queue the upcall. That prevents
 535	 * wake_up_process in the downcall from racing with schedule.
 536	 */
 537	set_current_state(TASK_UNINTERRUPTIBLE);
 538	ret = rpc_queue_upcall(pipe, &msg);
 539	if (ret < 0) {
 540		set_current_state(TASK_RUNNING);
 541		goto out;
 542	}
 543
 544	schedule();
 545	set_current_state(TASK_RUNNING);
 546
 547	if (msg.errno < 0)
 548		ret = msg.errno;
 549out:
 550	return ret;
 551}
 552
 553static int
 554cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg)
 555{
 556	int ret;
 557
 558	/*
 559	 * -EAGAIN occurs when pipe is closed and reopened while there are
 560	 *  upcalls queued.
 561	 */
 562	do {
 563		ret = __cld_pipe_upcall(pipe, cmsg);
 564	} while (ret == -EAGAIN);
 565
 566	return ret;
 567}
 568
 569static ssize_t
 570cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 571{
 572	struct cld_upcall *tmp, *cup;
 573	struct cld_msg __user *cmsg = (struct cld_msg __user *)src;
 574	uint32_t xid;
 575	struct nfsd_net *nn = net_generic(filp->f_dentry->d_sb->s_fs_info,
 576						nfsd_net_id);
 577	struct cld_net *cn = nn->cld_net;
 578
 579	if (mlen != sizeof(*cmsg)) {
 580		dprintk("%s: got %zu bytes, expected %zu\n", __func__, mlen,
 581			sizeof(*cmsg));
 582		return -EINVAL;
 583	}
 584
 585	/* copy just the xid so we can try to find that */
 586	if (copy_from_user(&xid, &cmsg->cm_xid, sizeof(xid)) != 0) {
 587		dprintk("%s: error when copying xid from userspace", __func__);
 588		return -EFAULT;
 589	}
 590
 591	/* walk the list and find corresponding xid */
 592	cup = NULL;
 593	spin_lock(&cn->cn_lock);
 594	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
 595		if (get_unaligned(&tmp->cu_msg.cm_xid) == xid) {
 596			cup = tmp;
 597			list_del_init(&cup->cu_list);
 598			break;
 599		}
 600	}
 601	spin_unlock(&cn->cn_lock);
 602
 603	/* couldn't find upcall? */
 604	if (!cup) {
 605		dprintk("%s: couldn't find upcall -- xid=%u\n", __func__, xid);
 606		return -EINVAL;
 607	}
 608
 609	if (copy_from_user(&cup->cu_msg, src, mlen) != 0)
 610		return -EFAULT;
 611
 612	wake_up_process(cup->cu_task);
 613	return mlen;
 614}
 615
 616static void
 617cld_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 618{
 619	struct cld_msg *cmsg = msg->data;
 620	struct cld_upcall *cup = container_of(cmsg, struct cld_upcall,
 621						 cu_msg);
 622
 623	/* errno >= 0 means we got a downcall */
 624	if (msg->errno >= 0)
 625		return;
 626
 627	wake_up_process(cup->cu_task);
 628}
 629
 630static const struct rpc_pipe_ops cld_upcall_ops = {
 631	.upcall		= rpc_pipe_generic_upcall,
 632	.downcall	= cld_pipe_downcall,
 633	.destroy_msg	= cld_pipe_destroy_msg,
 634};
 635
 636static struct dentry *
 637nfsd4_cld_register_sb(struct super_block *sb, struct rpc_pipe *pipe)
 638{
 639	struct dentry *dir, *dentry;
 640
 641	dir = rpc_d_lookup_sb(sb, NFSD_PIPE_DIR);
 642	if (dir == NULL)
 643		return ERR_PTR(-ENOENT);
 644	dentry = rpc_mkpipe_dentry(dir, NFSD_CLD_PIPE, NULL, pipe);
 645	dput(dir);
 646	return dentry;
 647}
 648
 649static void
 650nfsd4_cld_unregister_sb(struct rpc_pipe *pipe)
 651{
 652	if (pipe->dentry)
 653		rpc_unlink(pipe->dentry);
 654}
 655
 656static struct dentry *
 657nfsd4_cld_register_net(struct net *net, struct rpc_pipe *pipe)
 658{
 659	struct super_block *sb;
 660	struct dentry *dentry;
 661
 662	sb = rpc_get_sb_net(net);
 663	if (!sb)
 664		return NULL;
 665	dentry = nfsd4_cld_register_sb(sb, pipe);
 666	rpc_put_sb_net(net);
 667	return dentry;
 668}
 669
 670static void
 671nfsd4_cld_unregister_net(struct net *net, struct rpc_pipe *pipe)
 672{
 673	struct super_block *sb;
 674
 675	sb = rpc_get_sb_net(net);
 676	if (sb) {
 677		nfsd4_cld_unregister_sb(pipe);
 678		rpc_put_sb_net(net);
 679	}
 680}
 681
 682/* Initialize rpc_pipefs pipe for communication with client tracking daemon */
 683static int
 684nfsd4_init_cld_pipe(struct net *net)
 685{
 686	int ret;
 687	struct dentry *dentry;
 688	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 689	struct cld_net *cn;
 690
 691	if (nn->cld_net)
 692		return 0;
 693
 694	cn = kzalloc(sizeof(*cn), GFP_KERNEL);
 695	if (!cn) {
 696		ret = -ENOMEM;
 697		goto err;
 698	}
 699
 700	cn->cn_pipe = rpc_mkpipe_data(&cld_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
 701	if (IS_ERR(cn->cn_pipe)) {
 702		ret = PTR_ERR(cn->cn_pipe);
 703		goto err;
 704	}
 705	spin_lock_init(&cn->cn_lock);
 706	INIT_LIST_HEAD(&cn->cn_list);
 707
 708	dentry = nfsd4_cld_register_net(net, cn->cn_pipe);
 709	if (IS_ERR(dentry)) {
 710		ret = PTR_ERR(dentry);
 711		goto err_destroy_data;
 712	}
 713
 714	cn->cn_pipe->dentry = dentry;
 715	nn->cld_net = cn;
 716	return 0;
 717
 718err_destroy_data:
 719	rpc_destroy_pipe_data(cn->cn_pipe);
 720err:
 721	kfree(cn);
 722	printk(KERN_ERR "NFSD: unable to create nfsdcld upcall pipe (%d)\n",
 723			ret);
 724	return ret;
 725}
 726
 727static void
 728nfsd4_remove_cld_pipe(struct net *net)
 729{
 730	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 731	struct cld_net *cn = nn->cld_net;
 732
 733	nfsd4_cld_unregister_net(net, cn->cn_pipe);
 734	rpc_destroy_pipe_data(cn->cn_pipe);
 735	kfree(nn->cld_net);
 736	nn->cld_net = NULL;
 737}
 738
 739static struct cld_upcall *
 740alloc_cld_upcall(struct cld_net *cn)
 741{
 742	struct cld_upcall *new, *tmp;
 743
 744	new = kzalloc(sizeof(*new), GFP_KERNEL);
 745	if (!new)
 746		return new;
 747
 748	/* FIXME: hard cap on number in flight? */
 749restart_search:
 750	spin_lock(&cn->cn_lock);
 751	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
 752		if (tmp->cu_msg.cm_xid == cn->cn_xid) {
 753			cn->cn_xid++;
 754			spin_unlock(&cn->cn_lock);
 755			goto restart_search;
 756		}
 757	}
 758	new->cu_task = current;
 759	new->cu_msg.cm_vers = CLD_UPCALL_VERSION;
 760	put_unaligned(cn->cn_xid++, &new->cu_msg.cm_xid);
 761	new->cu_net = cn;
 762	list_add(&new->cu_list, &cn->cn_list);
 763	spin_unlock(&cn->cn_lock);
 764
 765	dprintk("%s: allocated xid %u\n", __func__, new->cu_msg.cm_xid);
 766
 767	return new;
 768}
 769
 770static void
 771free_cld_upcall(struct cld_upcall *victim)
 772{
 773	struct cld_net *cn = victim->cu_net;
 774
 775	spin_lock(&cn->cn_lock);
 776	list_del(&victim->cu_list);
 777	spin_unlock(&cn->cn_lock);
 778	kfree(victim);
 779}
 780
 781/* Ask daemon to create a new record */
 782static void
 783nfsd4_cld_create(struct nfs4_client *clp)
 784{
 785	int ret;
 786	struct cld_upcall *cup;
 787	/* FIXME: determine net from clp */
 788	struct nfsd_net *nn = net_generic(&init_net, nfsd_net_id);
 789	struct cld_net *cn = nn->cld_net;
 790
 791	/* Don't upcall if it's already stored */
 792	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 793		return;
 794
 795	cup = alloc_cld_upcall(cn);
 796	if (!cup) {
 797		ret = -ENOMEM;
 798		goto out_err;
 799	}
 800
 801	cup->cu_msg.cm_cmd = Cld_Create;
 802	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
 803	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
 804			clp->cl_name.len);
 805
 806	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
 807	if (!ret) {
 808		ret = cup->cu_msg.cm_status;
 809		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 810	}
 811
 812	free_cld_upcall(cup);
 813out_err:
 814	if (ret)
 815		printk(KERN_ERR "NFSD: Unable to create client "
 816				"record on stable storage: %d\n", ret);
 817}
 818
 819/* Ask daemon to create a new record */
 820static void
 821nfsd4_cld_remove(struct nfs4_client *clp)
 822{
 823	int ret;
 824	struct cld_upcall *cup;
 825	/* FIXME: determine net from clp */
 826	struct nfsd_net *nn = net_generic(&init_net, nfsd_net_id);
 827	struct cld_net *cn = nn->cld_net;
 828
 829	/* Don't upcall if it's already removed */
 830	if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 831		return;
 832
 833	cup = alloc_cld_upcall(cn);
 834	if (!cup) {
 835		ret = -ENOMEM;
 836		goto out_err;
 837	}
 838
 839	cup->cu_msg.cm_cmd = Cld_Remove;
 840	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
 841	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
 842			clp->cl_name.len);
 843
 844	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
 845	if (!ret) {
 846		ret = cup->cu_msg.cm_status;
 847		clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 848	}
 849
 850	free_cld_upcall(cup);
 851out_err:
 852	if (ret)
 853		printk(KERN_ERR "NFSD: Unable to remove client "
 854				"record from stable storage: %d\n", ret);
 855}
 856
 857/* Check for presence of a record, and update its timestamp */
 858static int
 859nfsd4_cld_check(struct nfs4_client *clp)
 860{
 861	int ret;
 862	struct cld_upcall *cup;
 863	/* FIXME: determine net from clp */
 864	struct nfsd_net *nn = net_generic(&init_net, nfsd_net_id);
 865	struct cld_net *cn = nn->cld_net;
 866
 867	/* Don't upcall if one was already stored during this grace pd */
 868	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 869		return 0;
 870
 871	cup = alloc_cld_upcall(cn);
 872	if (!cup) {
 873		printk(KERN_ERR "NFSD: Unable to check client record on "
 874				"stable storage: %d\n", -ENOMEM);
 875		return -ENOMEM;
 876	}
 877
 878	cup->cu_msg.cm_cmd = Cld_Check;
 879	cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
 880	memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
 881			clp->cl_name.len);
 882
 883	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
 884	if (!ret) {
 885		ret = cup->cu_msg.cm_status;
 886		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 887	}
 888
 889	free_cld_upcall(cup);
 890	return ret;
 891}
 892
 893static void
 894nfsd4_cld_grace_done(struct net *net, time_t boot_time)
 895{
 896	int ret;
 897	struct cld_upcall *cup;
 898	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 899	struct cld_net *cn = nn->cld_net;
 900
 901	cup = alloc_cld_upcall(cn);
 902	if (!cup) {
 903		ret = -ENOMEM;
 904		goto out_err;
 905	}
 906
 907	cup->cu_msg.cm_cmd = Cld_GraceDone;
 908	cup->cu_msg.cm_u.cm_gracetime = (int64_t)boot_time;
 909	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg);
 910	if (!ret)
 911		ret = cup->cu_msg.cm_status;
 912
 913	free_cld_upcall(cup);
 914out_err:
 915	if (ret)
 916		printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret);
 917}
 918
 919static struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = {
 920	.init		= nfsd4_init_cld_pipe,
 921	.exit		= nfsd4_remove_cld_pipe,
 922	.create		= nfsd4_cld_create,
 923	.remove		= nfsd4_cld_remove,
 924	.check		= nfsd4_cld_check,
 925	.grace_done	= nfsd4_cld_grace_done,
 926};
 927
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 928int
 929nfsd4_client_tracking_init(struct net *net)
 930{
 931	int status;
 932	struct path path;
 
 
 
 
 
 933
 934	if (!client_tracking_ops) {
 935		client_tracking_ops = &nfsd4_cld_tracking_ops;
 936		status = kern_path(nfs4_recoverydir(), LOOKUP_FOLLOW, &path);
 937		if (!status) {
 938			if (S_ISDIR(path.dentry->d_inode->i_mode))
 939				client_tracking_ops =
 940						&nfsd4_legacy_tracking_ops;
 941			path_put(&path);
 942		}
 943	}
 944
 945	status = client_tracking_ops->init(net);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 946	if (status) {
 947		printk(KERN_WARNING "NFSD: Unable to initialize client "
 948				    "recovery tracking! (%d)\n", status);
 949		client_tracking_ops = NULL;
 950	}
 951	return status;
 952}
 953
 954void
 955nfsd4_client_tracking_exit(struct net *net)
 956{
 957	if (client_tracking_ops) {
 958		client_tracking_ops->exit(net);
 959		client_tracking_ops = NULL;
 
 
 
 960	}
 961}
 962
 963void
 964nfsd4_client_record_create(struct nfs4_client *clp)
 965{
 966	if (client_tracking_ops)
 967		client_tracking_ops->create(clp);
 
 
 968}
 969
 970void
 971nfsd4_client_record_remove(struct nfs4_client *clp)
 972{
 973	if (client_tracking_ops)
 974		client_tracking_ops->remove(clp);
 
 
 975}
 976
 977int
 978nfsd4_client_record_check(struct nfs4_client *clp)
 979{
 980	if (client_tracking_ops)
 981		return client_tracking_ops->check(clp);
 
 
 982
 983	return -EOPNOTSUPP;
 984}
 985
 986void
 987nfsd4_record_grace_done(struct net *net, time_t boot_time)
 988{
 989	if (client_tracking_ops)
 990		client_tracking_ops->grace_done(net, boot_time);
 991}
 992
 993static int
 994rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr)
 995{
 996	struct super_block *sb = ptr;
 997	struct net *net = sb->s_fs_info;
 998	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 999	struct cld_net *cn = nn->cld_net;
1000	struct dentry *dentry;
1001	int ret = 0;
1002
1003	if (!try_module_get(THIS_MODULE))
1004		return 0;
1005
1006	if (!cn) {
1007		module_put(THIS_MODULE);
1008		return 0;
1009	}
1010
1011	switch (event) {
1012	case RPC_PIPEFS_MOUNT:
1013		dentry = nfsd4_cld_register_sb(sb, cn->cn_pipe);
1014		if (IS_ERR(dentry)) {
1015			ret = PTR_ERR(dentry);
1016			break;
1017		}
1018		cn->cn_pipe->dentry = dentry;
1019		break;
1020	case RPC_PIPEFS_UMOUNT:
1021		if (cn->cn_pipe->dentry)
1022			nfsd4_cld_unregister_sb(cn->cn_pipe);
1023		break;
1024	default:
1025		ret = -ENOTSUPP;
1026		break;
1027	}
1028	module_put(THIS_MODULE);
1029	return ret;
1030}
1031
1032static struct notifier_block nfsd4_cld_block = {
1033	.notifier_call = rpc_pipefs_event,
1034};
1035
1036int
1037register_cld_notifier(void)
1038{
1039	return rpc_pipefs_notifier_register(&nfsd4_cld_block);
1040}
1041
1042void
1043unregister_cld_notifier(void)
1044{
1045	rpc_pipefs_notifier_unregister(&nfsd4_cld_block);
1046}